The charter of the Audio/Video Transport (avt) working group in the Real-time Applications and Infrastructure Area of the IETF has been updated. For additional information, please contact the Area Directors or the working group Chairs. +++ Audio/Video Transport (avt) ============================= Current Status: Active Working Group Chair(s): Colin Perkins <csp@csperkins.org> Tom Taylor <taylor@nortel.com> Roni Even <roni.even@polycom.co.il> Real-time Applications and Infrastructure Area Director(s): Jon Peterson <jon.peterson@neustar.biz> Cullen Jennings <fluffy@cisco.com> Real-time Applications and Infrastructure Area Advisor: Cullen Jennings <fluffy@cisco.com> Mailing Lists: General Discussion: avt@ietf.org To Subscribe: https://www1.ietf.org/mailman//listinfo/avt Archive: http://www.ietf.org/mail-archive/web/avt/index.html Description of Working Group: The Audio/Video Transport Working Group was formed to specify a protocol for real-time transmission of audio and video over unicast and multicast UDP/IP. This is the Real-time Transport Protocol, RTP, together with its associated profiles and payload formats. The current aims of the working group are: - to review and revise existing payload formats to advance those which are useful to Draft Standard, and to declare others as Historic. Milestones will be established as a champion for each payload format is identified. - to develop payload formats for new media codecs, and to document best-current practices in payload format design. The group continues to be precluded from work on codecs themselves because of overlap with the other standards bodies, and because the IETF does not have the ability to effectively review new codecs. An exception was made for the freeware iLBC codec on a highly experimental basis, but acceptance of new codec work is unexpected and subject to rechartering. - to complete the forward error correction work to update RFC 2733 in the form of the ULP payload format - to extend RTP to work with Source-Specific Multicast sessions with unicast feedback - to provide a framing mechanism for RTP over TCP and TLS - in collaboration with the MPLS and ROHC WGs, to develop a solution for header compression of RTP across MPLS networks that avoid decompression and compression at each MPLS node. - to develop a new RTP profile for the combination of the SRTP profile and the Extended RTP Profile for RTCP-based Feedback (RTP/SAVPF) - to maintain and enhance the SRTP Profile, with review and input from the Security Area - to develop a new RTP profile for usage of TFRC (RFC 3448) with RTP over UDP to allow application developers to gain experience with TCP friendly congestion control. - to develop a MIB for RTCP XR (RFC 3611). - to update the RTP MIB, including aligning it with RFC 3550. - to clarify how RTP is used for media in conferencing with centralized nodes performing relay, translation or mixing of media. - to develop the mechanisms needed for efficient control of media and its encoding process in RTP based conferencing, both over multicast and transport containing relays, translators and mixers. An example of such a mechanism is a method to request a full intra coded frame of video. This would be used to allow joining participants to receive video immediately after joining instead of waiting for the next intra coded frame. It also allows mixers to perform switching between media sources without the need to re-encode the media. - to develop a solution for carrying media meta data, specifically SMPTE timestamps, to enhance the media stream. Such transport may be done in either RTP or RTCP depending on which is most suitable. The WG may consider if a generalized mechanism should be developed to enable future types of meta data to be easier to include. - to develop two new metric blocks for the RTCP XR (RFC 3611) framework to provide information on the media quality experienced by the receiver of RTP flows. One metrics block is for high resolution measurements of audio and speech quality. A second one for providing information on the quality of video. The timescale to complete this second block and the included metrics are highly dependable on the development of standardized subjective metrics for video quality. The WG will consider what metrics that are available and if they should be included or not. The metrics blocks shall not duplicate signaling information anyway necessary for the establishment of the session. The longer term goals of the working group are to advance the SRTP Profile, the Extended RTP Profile for RTCP-based Feedback, the Compressed RTP framework, and the RTP MIB to Draft Standard. The group has no plans to develop new RTP profiles beyond those listed above, but will consider rechartering to produce profile level extensions if appropriate. Goals and Milestones: Done Review DCCP including prototypes and API; feedback to DCCP WG Done Initial draft requirements for ECRTP over MPLS; discuss with MPLS WG Done Submit iLBC payload format for Proposed Standard Done Submit iLBC codec specification for Experimental Done Advance RTP specification and A/V profile to Full Standard Done Submit RTP/SAVPF profile for Proposed Standard Done Finished investigation of advanced FEC codes for RTP, update plan Done Submit extensions for RTP HC on MPLS networks for Proposed Standard Done Submit ULP Payload Format for Proposed Standard Aug 2006 Submit SMTPE Timestamping of Media for Proposed Standard Sep 2006 Submit RTCP/SSM draft for Proposed Standard Nov 2006 Submit "use of AES-192 and AES-256 in SRTP" for Proposed Standard Nov 2006 Submit update of RTP MIB for Proposed or Draft Standard Nov 2006 Submit RTCP XR MIB for Proposed Standard Nov 2006 Submit RTP Profile for TFRC for Proposed Standard Nov 2006 Submit RTCP XR High Resolution Audio Metrics for Proposed Standard Nov 2006 Submit Codec Control Messages for Proposed Standard Mar 2007 Submit SRTP for Draft Standard Mar 2007 Submit RTCP XR Video Metrics block for Proposed Standard Sep 2007 Submit RTP/AVPF for Draft Standard _______________________________________________ IETF-Announce@ietf.org https://www1.ietf.org/mailman/listinfo/ietf-announce
